Credentialed NIDDK clinical staff members have relevant expertise necessary to support patient care needs of human subjects involved in clinical research conducted by all institutes and centers in the intramural research program. Consultative interactions provided by NIDDK clinicians with expertise in the fields of diabetes, endocrinology, metabolism, gastroenterology, hepatology, nephrology and hematology are required for delivery of specialized medical services to patients throughout the Clinical Research Center at NIH. Beyond patient support services, these consultative interactions lead to collaborative clinical investigations to advance the study of natural history of disease, new approaches to diagnosis and treatment, as well as advancing the understanding of disease pathogenesis and pathophysiology. Clinical services include: 1. Blood Glucose Management Service involves comprehensive management of patients with insulin deficient or insulin resistant diabetes mellitus. 2. Consultation services in endocrinology, gastroenterology, hepatology, nephrology, cystic fibrosis and hematology. 3. Gastrointestinal endoscopy, including biopsies and therapeutic procedures 4. Liver biopsies and liver fibroscanning 5. Renal biopsies, hemodialysis, continuous veno-venous hemofiltration, specialized research renal function tests 6. Biorepository: collection, barcoding, indexing, storing, and retrieving human samples 7. Biostatistical support for developing, monitoring, analyzing clinical research protocols Examples of completed and ongoing collaborative clinical research projects emerging from consultation services and clinical core services include: 1. Endocrine, gastrointestinal, liver and kidney complications of immunotherapy of metastatic melanoma, stem cell transplantation, chemotherapy and novel biologic anti-tumor agents (NCI, NHLBI); 2. Gastrointestinal complications of graft versus host disease (NHLBI, NCI, NIAID); 3. Liver complications of chronic granulomatous disease (NIAID), Hermansky-Pudlak syndrome (NHGRI) and cystinosis(NHGRI); 4. Natural history and management of kidney and liver complications of sickle cell anemia (NHLBI); 5. Renal complications of HIV disease and HIV drug therapies (NIAID); 6. Kidney manifestations and effects of recombinant enzyme treatment of Fabry disease (NINDS); 7. Membranous nephropathy in patients with non-myeloablative stem cell transplants (NHLBI); 8. Renal vasculitis in Wiskott-Aldrich syndrome (NHGRI); 9. Endothelial injury and thrombotic microangiopathy in stem cell transplants (NHLBI, NCI, NIAID)